Re: Flying Rio Grande Logo.

Unless dated D&RGW AFE's indicating a change in herald application have remained extant until some researcher could go through the tedium required in the sorting process... I suspect exact dates might be a wee bit difficult for the "K" Class locomotives listed...
The following is a listing of some of these locomotives photographed within one weeks time during the transition period of August 1940... K-37 #495 on 8/13/1940 at Salida with "Flying Grande" scheme and well sooted smoke box sides (not smoke box door)... - K-37 #498 on 8/13/1940 at Salida with "Flying Grande" scheme and only light weathering... - K-28 #479 at Salida 8/14/1940 uniformly clean with crisp "Flying Grande" scheme... - K-37 #490 on turntable at Sargent 8/14/1940 with spotless fresh paint and late 30's herald & lettering... - K-28 #474 taking on water at the Crested Butte tank 8/14/1940 in fresh spotless paint and late 1930's herald & lettering... - K-37 #492 at Gunnison on 8/15/1940 with "Flying Grande" scheme, front dual gauge coupler pocket casting, and light weathering... - K-37 #493 with late 30's herald and lettering leading K-37 #499 in "Flying Grande" scheme at Gunnison on 8/15/1940 * Both showing equal amounts of general weathering * - K-37 #496 with "Flying Grande" scheme at Gunnison on 8/15/1940 with its dual gauge pilot coupler casting and slightly less weathering than the above two units... - K-37 #499 with "Flying Grande" scheme at Gunnison on 8/15/1940 with above listed weathering... - K-28 #475 coming into Durango with a freight train on 8/17/1940 with crisp late 30's herald & lettering and some weathering on the front... - K-28 #476 with San Juan at Durango on 8/18/1940 with crisp late 30's herald & lettering and some weathering on the front... - K-28 #477 with San Juan at Carracas on 8/18/1940 with crisp late 30's herald & lettering and slight weathering... - K-36 #486 at Chama with "Flying Grande" scheme on 8/18/1940 with light uniform weathering throughout...
For a more comprehensive listing of the K-27 locomotives herald & lettering schemes see recent on the On3 Yahoo Group... Cordially... John